I don't think what the author did here (descreening) has anything to do with Moire per se. Sure, due to the nature of halftone, it often introduce Moire as the author said. But if you scan your document/photo at high enough resolution (sampling theorem anyone?) it isn't an issue in the descreening process later (which is the main topic of this article.)
Also, using inverse fourier transform to descreen is already the basis of lots of popular commercial denoise plugins (for Photoshop etc.). Most of them will automatically measure the angle and resolution of halftone matrix too.
I assumed that the issue was less the scanning (which can be extremely high precision, and, in any case, the author had to do to get the half-tone image he was working with) but the printing. Once the image is resized and printed in the book, the offset between the dpi of the printer and the half-tone dots was going to introduce new artifacts.
Also, using inverse fourier transform to descreen is already the basis of lots of popular commercial denoise plugins (for Photoshop etc.). Most of them will automatically measure the angle and resolution of halftone matrix too.